#include <stdio.h>

int main()
{
    int urn[5] = {100, 200, 300, 400, 500};

    int *ptr1, * ptr2, * ptr3;

    ptr1 = urn;
    ptr2 = &urn[2];

    printf("pointer value, dereferenced pointer, pointer, pointer address:\n");
    printf("ptr1 = %p, *ptr1 = %d, &ptr1 = %p\n", ptr1, *ptr1, &ptr1);

    ptr3 = ptr1 + 4;
    printf("\nadding an int to a pointer:\n");
    printf("ptr1 + 4 = %p, *(ptr1 + 4) = %d\n", ptr1 + 4, *(ptr1 + 4));

    ptr1++;
    printf("\nvalues after ptr1++:\n");
    printf("ptr1 = %p, *ptr1 = %d, &ptr1 = %p\n", ptr1, *ptr1, &ptr1);

    ptr2--;
    printf("\nvalues after ptr2--:\n");
    printf("ptr2 = %p, *ptr2 = %d, &ptr2 = %p\n", ptr2, *ptr2, &ptr2);

    ptr1--;
    ptr2++;
    printf("\nPointers reset to original values:\n");
    printf("ptr1 = %p, ptr2 = %p\n", ptr1, ptr2);

    printf("\nsubtractiong one pointer from another:\n");
    printf("ptr2 = %p, ptr1 = %p, ptr2 - ptr1 = %td ptr1 - ptr2 = %td\n", ptr2, ptr1, ptr2 - ptr1, ptr1 - ptr2);

    printf("\nsubtractiong an int from a pointer:\n");
    printf("ptr3 = %p, ptr3 - 2 = %p\n", ptr3, ptr3 - 2);
}
